whats best boiler temp

bruce_18

thanks for responding , no air or flow problem , old boiler was tankless so temp was higher , base boards ran hotter and it just seemed more efficint to me, i figure if you start boiler up from room temp to 180 how much do you lose/gain going to 200

bruce_18

boiler temp

installed a crown twz series boiler last year , radiator output seems cooler than before , boiler set at 180 , what can i raise that temp. up too , or what should it be ???

Brad White

Let's step back a bit, Bruce

Just want to cover some bases first.

Same radiation as before? Is it airbound? I mean, the weather in most places has been well above design minimums, so if you have a problem now, just wait. Where are you, geographically speaking?

Other questions: Do you have OD Reset? Obvious but I have to ask if the radiation might be de-coupled and run at a lower temperature.

Is your perception that "the radiation seems cooler" also mean that "the house is cooler"? Is it everywhere or just isolated such as at upper floors, remote bedrooms, that darned enclosed barely insulated porch....

180F is a "traditional" high temperature but 200F is another commonly catalogued. I would hate to see you go there in what has to be mid-range seasonal temperatures. Let's look somewhere else for other issues such as air binding, poor flow, closed valves, pipe gremlins....

jp_2

flow problem?

sounds like a flow problem, with this mild winter, 180F should be plenty.

Brad White

At 180F

going in and a 20 degree drop (170 Average Water Temperature) you will get 150 BTUH per SF of EDR.

If you raise this to 200 going in, 190 Average Water Temperature, the output will rise to 190 BTUH per SF of EDR, one place the numbers align. This is a 26.6% increase.

In between, 190-170 a 180F average, you will get 170 BTUH per SF of EDR, a 13.3% increase.

By "hotter" it would not be "more efficient" except in the sense that the space was perceived as warmer.

What is the space temperature anyway? You should be able to crank the space temperature up a good ways above setpoint as a test. Have to find that chart....

Ken D.

Temp

I know this sounds condesending, but it is a problem many times. Is the circualtor pumping in the right direction? Does the boiler cycle off on high limit? if so, it sounds like a flow problem to me too. Any chance there are valves closed down?

jp_2

also,

for the heck of it, what are your rad temperatures?

if you have high pipe losses, upping the temps up the losses.
check your supply pipes.